dna the blue print of life
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DNA the Blue Print of Life. Biology 10. Understand that DNA is the Blue Print or Code that Controls all activities in living creatures Growth Repair Hormones Enzymes Eye color Behavior Hair color ……. You Probably know DNA like this. DNA Developed you from this. Head. Spine. To This. - PowerPoint PPT PresentationTRANSCRIPT
DNADNAthe Blue Print of Lifethe Blue Print of Life
DNADNAthe Blue Print of Lifethe Blue Print of Life
Biology 10Biology 10
Understand that DNA is the Blue Print or Code that Controls
all activities in living creatures
1. Growth
2. Repair
3. Hormones
4. Enzymes
5. Eye color
6. Behavior
7. Hair color
……..
You Probably know DNA like this
DNA Developed you from this
Head
Spine
To This
Into this - Yikes
But How did they ever discover DNA?
The story begins with a curious experiment conducted by Dr. Griffiths
with white mice…….
What was killing these Mice?
Hershey-Chase Experiment
Researchers had to determine if DNA was genetic material and not protein
1. Was it DNA or proteins that was the genetic material?
2. Bacteriophages - viruses useda. protein coatb. nucleic acid interior (DNA
core)
3. Radioactive labeling of protein & DNA
4. Results showed that DNA directed the formation of new viruses, not the protein coat
Discovery of DNA Structure
Components of DNA 1. DNA consists of a sugar,
base and phosphate group
2. One of 4 possible bases:
adenine (A)cytosine (C)guanine (G)thymine (T)
DNA Structure – The Twisted Ladder
The Nucleotide:
1. Sugar
2. Phosphate Group
3. Nitrogenous Base
Ribose Sugar
Phosp
hate
Base
Experiments – 1949
1. the amount of A = amount of T
2. the amount of C = amount of G
3. ratios vary by species
X-Ray experiments
1. Used X-rays to examine structure of DNA
2. Observed thata. DNA is helicalb. DNA exists in long
strandsc. DNA is highly repetitive
Watson-Crick Analysis of DNA 1. Constructed a model of DNA
structure 2. Phosphate groups from backbone3. Double-stranded molecule4. Base=pairing of A-T and G-C5. Helical shape
DNA Replication & Repair
A. Replication 1. replication is semi-conservative2. major molecules
a. unwinds DNA strandsb. DNA polymerase - copies DNAc. molecular glues seal newly
formed DNA strands
B. DNA Repair
1. DNA polymerase “proofreads” the new strands
2. Glues help to repair mismatched bases
DNA OrganizationA. Chromosome structure
1. DNA is organized into long molecules called chromosomes
2. Chromosome are stabilized by proteins called histones
3. Histones organize the DNA
DNA has been Mapped – E. Coli DNA
Plants have been able to Clone themselves and their DNA
forever
Scientists Did this with Sheep
The Human Genome Project
Science Fiction?Science Fiction?